Machine for forming solid carbon dioxide



. Oct. s, 1940. RHILL 2,27,.s9

MACHINE. FOR FORMING SOLID CARBON DIOXIDE Original Filed Nov.- 29, 19372 Sheets-Sheet 2 attorneg Patented Oct. 8,

Reuben Hill, Los Angeles, Calif., assignor to Leo M. Harvey, La Canada,Calif.

Application November 29, 1937, Serial No. 171.048

- Renewed June 23, 1939, v

17 Claims. (Cisa-121 This inventin relates to machines tor forming solidcarbon dioxide. L

In order to maintain refigeration of a container, andmore particularlyone requiring trans portation, it is a common practice to sdispose thecontainer in a pa'cking formed by blocks or ragments of ice or otsolidified carbon dioxide.

such practice consumes considerable time in preparing and positioningsuch packing, and the interstices between the blocks or fragments, andbetween the packing and the container materially detract from therefrigerant efiect and also re- Q duce the hold-over interval or periodof refrigeration.

solidifying carbon dioxide, asa continuous mass,

in intimate and continuous contact with a container, so as to cool thelatter with a maximum emciency and oier a maximum resistance .tosublimation. i

Another object is to provide a machine for depositing a jacket of solidcarbon dioxid'e in a substantially surrounding relation to a container,

imposing a very low temperature upon the container and its contents, andeliminating the time and labor requiredin prior methods of applyingrefrigerant packings, and minimizing required refrigerant. e i i Anotherobject is to form a reirigerant space between' an inner and an outercontainer, and toprovide for the 'delivery of liquid carbondioxide tosuch space, and the consequent tormation therein of a jacket orsolidcarbon dloxide for maintaining a prolonged low temperature cooling ofthe inner container.

' A further object is to provide for a 'ready removal oi the innercontainer from the outer one,

to iacilitate loading or unloading of the inner container. g 40 Afurther object is to provide a machine comprising an enclosure wherein acontainer may be' `;acketed with solid carbon dioxide, said machinecomprising, valve mech'anism for controlling the flow of fluid carbondioxide to such enclosure. A further object is to provide !or a'di'scharge from such chamber in gaseous form, of such carbon dioxide asfalls to solidity, and to utilize such gaseouscarbon dioxlde inprecooling liquid carbon dioxide delivered to said chamber.

These and various other obj'ects are'attained by the constructionhereinaiter described, and' illustrated in the accompanying drawings,'where- 55 elevation.

Fig 1 is a view oi the improved machine in side Fig. 2 is an isometricview of a package, com prising inner and outer containers showng theinner' one partially withdrawn from the outer.

Fig. 3 is a cross sectional view, taken on the'line 3-3'of Fig. 1, andshowing said containers, as inserted in a 'receiver stationaryon thema-- chine. v

Fig. 4 is another isometric view of said package, as seen from the rear.g

Fig. 5 is a cross sectional View, taken 'on the line' 5-5 of Fig. 1,showing valve mechanism controlling the flow of liquid .carbon dioxide.

. In these views, the reference character l designates a rectangularreceiver, adapted to form 'An object' of the invention is toprovide forv an enclosure for a package or receptacle com- 15 prising inner andouter containers 2 and 3, .which are also preferably rectangular; 'saidreceiver and the outer container are formed preferably of a heatinsulating material such as are common, and the inner container isformed of sheet metal, zo sufllciently thin to readily transmit heat.Doors 4, 5, and 6 serve to give access to the front ends of the receiverI, and to the inner and o'utercontainers, said doors being preferably'hinged and 4 The' outer con- 25 walls, and spacer blocks 8 areinteriorly attached to the door .and rear wall of such container. saidstrips and blocks are preferably so proportioned as to provide ior equalspacing of all walls of the two containers'. V

For delivering liquid carbon dioxide into the space between thecontainersz and 3, one or more nozzles 9 are carried by and forwardlyproject from a circular manifold l0,.exteriorly secured Y to the tearwall of the receiver I, four ot such nozzles being preferablyemployed,as illustrated.

'These nozzles pass snugly through the receiver I, and projectthrough'oversize openingsil in the rear wall of the container 3, so asto 'freely extend some distance between the sidewalls and top and bottomwalls of the two `containers. Liquid carbon dioxide is delivered tothemanifold through 'a coil |2 from an expansion chamber IS, and a deliveryconnection ll to said chamber leads out of a housine ii !or valvemecbanism controlling the flow. It is preferred to further employ saidhousing as'a base for the receiver l, and to enclose the manifold o,coil l2, and expansion chamber' !3 in a hood IS, formed of heatinsulating material, and preferably mounted jointly on the rear endportions of the receiver and said housing.

Valve mechanism within the housing IE (see Fig. 5) comprises a baseplate I'l, a valve casing I 3 carried by such base plate, a valve memberl9 controlling flow through said casi'ng, a lever 20 pivoted on the baseplate at 2| and effective at one end on the nee'dle` va1ve,'aspring-pressed plunger 22 hearing on the other end portion of saidlever, and tending to close the valve, and a lever 23 for opening 'thevalve, pivoted 'on the base plate and rigidly carrying at its pivotalaxis a pinion 24, meshing with a rack bar 25, slidably guided on thebase plate.- An end portion of said rack bar is slotted lengthwise toaccommodate a pin 25 carried by the lever 20, said slot pernitting therack bar and its actuating lever to be returned immediately by a spring21 to a normal position, after the valve member s has been fullyunseated. For holding the valve member unseated, a. latch arm 28,pivoted at 29 on the base plate, is formed with a sear 30 and is actedupon by a spring` 3l, serving to engage the sear 30 with sear 32 on thelever 20, on shifting of the latter to its valve-opening. position. Itis preferred to form the latch arm with an extension projecting throughan opening 33 in the housing- I 5, said extension serving as a trip'armto permit of manual unlatching of the valve member, if desired. Theopening 33 also serves to allow the actuating lever 23 to project fromthe housing IS V to permit'of its convenient manipulation.

The valve mechanism further, comprises a device, mounted on the baseplate l'l for automatically tripp g the latch arm 28, after apredetermined lapse of time, to permit closing of the valve. Asdisclosed in Fig. 5, this device employs a plunger 34, operativelyengaged, at its mid portion `by one endof a. lever 35, whereof theother'end is operativ'ely connected by a link 36 to an arm 31 on theactuating lever 23. such 'connection is preferably establi'shed byengaging a pin 38 on said arm in aslot 39 of the link, thus avoidinginterference with automatic' recovery by the lever of its normalposition, following a Valveopening control. The lever is pivoted betweenits ends on the base plate, as indicated at' 40 and carries, between itspivot and link-engaging end a roller 4l, adapted to coact with thespringpressed end portion of the latch arm 28" to trip the latter,responsive to a certain rocking of such lever. One end of the plunger 34is under pressure of a coiled spring 42, whereby a piston43 on the otherend of said plunger and working in a dash-pot cylinder 44, is urgedtoward 'an end wall of such cylinder. Adioining such cyliudeiis achamber 43 from which a restricted pa'ssage 43 opens through said endwall, the degree of re-- strlction being preferabiy regulable by ametering A suitable liquid, preferably oil, oocu pies the space betweenthe piston 43 and said -cylinder end wall and aso`fllls the chamber 43,

v at least to thelevel of the passage' 45. Upon 'retraction of thepisten from said cylinder end wall,

liquid may'be'freely drawn into the cylnder from ,the chamber 45,' byway of a port (Fig. 5) controlled by .a check valve 48, spr -prema tore-'- sint outfl'ow. Approach of the pistonto the cylinder end wallimposes a pressure on the liquid in the cylinder that supplements thecheck \valv e more. of the corks 32 will yield the piston may notapproach the cylinder end wall faster than the trapped liquid escapesthrough the passage 46.

While any suitable source of liquid carbon dioxide may be employed, itis preferred to cradle a tank 49 of such liquid' on a stand 50 whichmountsthe machine at a. convenient elevation. such tankis terminallyprovided with a valved fitting 5l from which a delivery connection 52;preferably flexible, leads to the valve casing 18.

To cradle said tank, as described, it is preferred to invert the tankand engage its valved end with a recessed main support 53, which isapertured to" accommodate the fitting 5l, and is equippedwith a pair ofopposed trunnions 54, journaled in cross bars forming a lower portion ofthe stand. When thus engaged with said main support, the tank may bereadily tilted to laterally rest against a bar 55 terminally engaging a"pair of hooked .keepers 56 carried .by thegstand 59 respectivelysurmounting said receiver and,

the hood I 64. Gas failing to form snow escapes fromthe container 3through the openings |,l and fiows between said container and thereceiver to the vent duet 51. As best appears in Fig. 4, a

channel 60 may extend in the top wall of the container 3 from the rearedge to the center portion of said wall, to facilitate the escape ofgas.

A vent SI in -the bottom of the hood IS serves to discharge gas to theatmosphere. Since the gasthus passed through the hood is at very lowtemperature, it effectively precools the liquid carbon dioxide flowingthrough the expansion chamberT3' and coil I2. The chamber l3, inafl'ording the car-bon dioxide a'. limited expansion before reaching thenozzles, also exercises a precooling efl'ect. and the manifold nprovides for a still further -precoolng, in affording additionalexpansion of the carbon dioxide. In case; for any reason, the describedprvision for a free escape of gas fails to function, the resultantbuildingup 'of gas pressure will disengage th duct 51 froni one or bothof the flttings 58 and' 53 to relieve such pressure.

Fig.. 4* illustrates how the openings I l in the receiver 3 may-be clowdby corks 62 or the like,

after removal of 'a charged package from the ma-- china. This preventsaccess of relatively warm air to the charge of solid carbon dioxide, andre tains in the package cold gas 'resulting-from sublimation.. 'In casegas accumulated in a pack-` age acquires 'any considerable pressfe. oneor to relieve such pressure. e V

In operation of the machine. after insertion n the receiver of one ofthe packages comprised by the containers 2 and 3, and after closingof'the doors 4, I, and 3, the lever 23 is downwardly rocked by 'theoperator, until the sears of the latch arm' 23. and le'ver 23interengage to latch the valve member clear of its seat. This actuatio'nof the lever 23 is further'eflective, through the link 33 and lever 33,to shift the plmger 34 from its illustrated postonxmg. 51, to a position(not shown) compressing the spring 42 and shifting the' piston 43"towardthe open 'end of its. cylinder. Buch travel of the piston'draws aconsiderable charge in a frozen or other refrigerated state, the maofliquid into the cylinder, the 'check valve yielding to admit same. Uponrelease of the lever 23, the spring 42 immediately initiates a returntravel of the plunger, and the time required to complete such travel isdetermined by the setting of the metering pin 41, since this controls-the' rate of liquid discharge from the cylinder. As the plungercomplets its return travel, the roller 4! trips the latch .arm 28, andthe valve member is immediately seated, responsive to the spring-pressedplunger 22.

Thus it is seen that the valve`mechanism is semi-automatic in itsoperation, the valve being manually opened, and automatically latched inopen'position, and closing of the valve occurring automatically upon apredetermined lapse of time.

Opening of the valve establishes a flow of liquid carbon dioxide to thenozzles 9, and in its discharge into the space between the containers 2and 3, gasiiication of the liquid follows from relief of pressure.lifhis change of .form is productive of an intense cooling effect,resulting at once in a further transformation of the major portion ofthe carbon dioxide into snow particles. These adhere to the spaced wallsof the two containers, rapidly accumulating thereon "until the entirespace is occupied by a mass of tightly packed carbon dioxide-snow. Thedash-pot timing device will be regulated to automatically cut off carbondioxide delivery upon a time lapse, sufiicient for formation of thedescribed charge of snow.

When the machine is employed to refrigerantly charge a considerablenumber of similar packages, of the type shown in Fig. 2, a regulation ofthe timing device to suit one thereof, sufiices for all, Since the"holdoverfi or prolongation of refrigerant'efiect, is dependent on theVolume of snow with which a packageis charged by the machine, it followsthat packages may be designed with difierent accommodations for snow, topre'- determinedly differentiate their, holdover periods. Adjustment 'ofthe metering pin 41 permits of radily regulating the period ofcarbondioxide flow to conform withthe charging capacity of anyparticular package orlgroupof packages.

In event of failure of the automatic features of the machine, or if, forany reason, an operator desires to interrupt a package-chargingoperation, the exterior extension of the latch'arm 28 permits ofmanually cutting off the flow of carbon dioxide.

The charging of packages with a refrigerant, as-

described, is useful in various ways A package so charged assuresmaintenance of a predetermined ly low temperature ,within the innercontainer for a definite period, 'which may be predetermined to protectperishable. commodities throughout shlpment to a certain destination.The protective temperature may be above or below the freezing point ofthe commodities, according tothe design of the package. i

If it is necessary for a consignee to further prolong refrigeration oficommodities delivered to him chine readily permits of such prolongationlDehydrationof commodities by the carbon di- ;oxide is prevented byscaling of the former from .the latter, within the innermetalliccontainer.

- While a rectangular package has been shown and described, it isapparent that the receiver I may be designed to accommodate packages ofany other shape.

The invention is presented as including all such modifications andchanges as come within the scope of the following claims.

What I claim is: r

1. A machine for forming solidified carbon dioxide comprising a chamberfor receiving a package formed with a space for the reception of therefrigerant, a .nozzle 'for discharging carbon dioxide into said space,a duct for delivering carbon dioxide to the nozzle, a valve controllingthe nozzle, means normally urging the valve to itsclosed position, alatch operable to hold the valve open, a time controlled device forreleasing the latch after a predetermined interval of time, and meansfor opening the valve operable to condition said device for operation.

2. A machine for forming solidified carbon dioxide comprising a chamberfor receiving a package formed with a space for the reception of therefrigerant, a manifold at the exterior of the chamber, spaced nozzlescommunicating With the manifold and adapted to discharge into saidspace,'a hood housing the manifold, a Conduit conducting carbon dioxideto the nozzles and 'passing through the housing, a valvecontrolling inthe conduit.

3. A machine for forming solidified carbon dioxide comprising a chamberfor receiving a package iorrned with a space for the reception of therefrigerant, a duct for delivering carbon di-.

oxide to said space 'to refrigerate' the same, a coil interposed in theduct, a valve controlling the duet, and an automatic control mechanismfor the valve.

4. A valve mechanism comprising a valve, a control lever for thevalve,'spring means acting 'on the lever to close the valve, a shiftablepart 'for Operating the valve, a latch releasably engageable with thepart to hold the valve open,' 'and time delay means for retardantlyreleasing the latch,

5. A machine for forming solid carbon dioxide comprising a chamberwherein the solidification occurs, me'ans for conduc'ting fluid carbondioxide to the chamber, a valve controlling the conducting means, meansnormally closing the valve, a latch for holding the valve open, a timingmechanism for releasing the latch after a predetermined time interval,and a common means for opening the valve and conditioning said timingmechanism for operation.

6. A machine for forming solidified carbon dioxide comprising a chamberfor receiving a package forme of the refrige ant, said chamber'having anadmission opening through which the package may be inserted andwithdrawn, a. closure for the opening, a. nozzle discharging in thechamber positioned to supply carbon dioxide to said space when thepackage is arranged in the chamber, and 'means for conducting carbondioxide to the nozzle.

. `7. A machine for refrigerating packages comprising a chamberforlreceiving a, package, nozzle means for discharging fluid carbondioxide into the package' in the chamber, a line .conducting carbondioxide to the nozzle* means, valve' means' controlling said line, meansnormally yieldingly closing the valve means, means for opening the valvemeans, and means made' operative by actuation of the last named means;for delaying.

the cloing of the valve means.

'8. A machine for refrigerating packagescomprising a chamber forreceiving a package, nozzle means for discharging fluid carbon dioxideinto with a space for-the reception the package in the chamber, a lineconducting carbon dioxide to the nozzle means, valve means controllingsaid line, means.normally yieldingly closing the valve means, means foropening the valve means, and dash pot means made operative by actuationof the last`named means for delaying the closing of the valve means.

9. A machine for rei'r'igerating packages com'- prising a chamber forreceiving a package, nozzle means for discharging fluid carbon dioxideinto the package in the chamber, a line conducting carbon dioxide to thenozzle means, valve means controlling said line, means normallyyieldingly closing the valve means, Operating means for opening thevalve, time delay means for delayingthe closing of the valve means, andan operative connection between the Operating meansand the time delaymeans conditioning the time delay means for operation when the valvemeans is opened and f'ein'g the Operating means for return uponconditionin of the time delay means.

10. In a device tor !orming s'olidifled carbon dioxide, nozzle means fordischarging carbon dioxide, means !or conducting fluid carbon dioxide tothe nozzle means, valve means controlling the -conducting means, meansnormally yieldingly holding the valve .means closed, releasable means!or holding the valve means open, Operating means for opening the valvemeans' and putting the releasable holding means into operation, and timedelay means tor releasing the releasable holding means at the end of apredetermined interval of time.

11. In,a device for forming solidifled carbondioxide, nozzle means fordischarglng carbon dioxide, means for conduct'ing fluidtcarbon dioxideto the nozzle means, valve means controlling the conducting means, meansnormally yieldingiy holding the valve means-closed, releasable means forholding the valve means open, Operating means for openingthe valve'meansand putting the releasable holding means into operation, and time delaymeans 'for releasing the releasable holding means at the end of apredetermined interval of time, the time delay means including manuallyregulable means for varying said intervaL 12. A machine -forrefrigerating a package I) comprising a receiver i'or the package,nozzle means for' discharging carbon dioxide into the ackage when thepackage is in position in the eceiver, a line conducting fluid carbondioxide to the nozzle means, means interposed in said lineallowingpartial expansion of the carbon dioxide, a housingenclosing saidinterposed means. and means tor conducting the carbon dioxide to thenozzle means, a coil interposed in said line,

a housing enclosingthe coil, and means for conducting the carbondioxidethat falls to solidify in the package i'rom 'the receiver to thehousing I to cool the coil.

14. In a device for !orming solidifled carbon dioxide, discharge meansfor discharging the carbon dioxide, valve means for controlling thedischarge means, means urging the valve means to the closed position,Operating means for open- 'ing the valve means, releasable means Io'rholding thevalve means open, time delay means operablejto release saidreleasable means after a given time interval, and means for restoringthe Operating means after operation.

. 15. Adevice for refrigerating a package having an inner container andan outer container arranged around the inner container to leave a spacebetween the container, the device com-- prising a receiver having anopening for receiving and positioning the package, discharge means Vpositioned to discharge carbon dioxide into said space when the packageis positioned in the opening," and means controlling the dischargemeans.-

16. A device for refrigerating` packages' com prlslng a receiver havinga chamber for receiving a package, the chamber being shaped to cooperatewith the package to hold the same in a given position, discharge meansfor discharging.

carbon dioxide into the package when the package is -ln-the chambeu anda control for the discharge means.

17. A device tor reirigerating packages comprising a receiver having achamber for receiving a package, the chamber being shaped `to cooperatewith the package to' hold the same in a given position, discharge meansfor discharging carbon -dioxide into the package when the package is inthe chamber, and a manually conditioned time governed control tor thedischarge means operable to' cause the discharge` of carbon dioxide tora given period.

